Lexatumumab Tolerated for Pediatric Solid Tumors

(HealthDay News) – Lexatumumab, an agonistic, full human monoclonal antibody against tumor necrosis factor-related apoptosis-inducing ligand receptor 2, is well tolerated and may lessen certain clinical symptoms in some pediatric patients with solid tumors, according to a study published online Oct. 15 in the Journal of Clinical Oncology.

Melinda S. Merchant, M.D., Ph.D., from the National Cancer Institute in Bethesda, Md., and colleagues conducted a phase I dose-escalation study to examine the safety, tolerability, pharmacokinetics, and immunogenicity of lexatumumab for recurrent or progressive solid tumors. Doses of 3, 5, 8, and 10mg/kg were administered once every two weeks to 24 patients age 21 years of age and younger.

The researchers found that, over all four planned dose levels, the patients received a total of 56 cycles of lexatumumab. During the second cycle, one patient had grade 2 pericarditis consistent with radiation recall and one patient developed grade 3 pneumonia with hypoxia. For three to 24 cycles, five patients experienced stable disease. There were no complete or partial responses but evidence of antitumor activity was noted in several patients, including one patient with recurrent progressive osteosarcoma who experienced resolution of clinical symptoms and positron emission tomography activity, which was ongoing more than one year after cessation of therapy. There was a dramatic biomarker response seen in one patient with hepatoblastoma.

"In conclusion, this study demonstrates that lexatumumab is well tolerated in heavily pretreated pediatric patients with solid tumors," the authors write.